In my project all worked fine.
But the hooked application crashed when calling LhUninstallAllHooks().
It was difficult to find the reason.
I found it finally:

If you link with Easyhook.lib you MUST use the Debug compiled Lib file if you compile your DLL as Debug. If you try to use the Release compiled Easyhook.Lib in a Debug compiled DLL file you will get a crash when calling LhUninstallAllHooks() although everything else works perfectly!